A dye composition for color photography



Patented Aug. l7, i948 A DYE CGWOSKTHON FOR CULOR PHG'EOGRAPHY and M. Had, and Frank J.

Harold C. Harsh, Rich Kaszuba, Binghamton, N. 2.,

asslgnors to Gen- N. Y a corporation of Delaware oral Aniline & Film Corporation, New York,

No Drawing. Application August 31, 1944, Serial No. 552,210

1 Claim. (m. 108-22) In preparing colored'drawings from an original black line or monochrome drawing, the

process employed is to copy or photograph a black and white or monochrome drawing on a photographic film. After development, washing and drying of the exposed film, the negative is laid on a glass illuminated from below and dye coating solutions applied to the transparent lines and areas of the negative which are to appear in color in the finished print. The colors of the dye solutions employed are complementary to the colors desired in the final print. To obtain in the final print, a line or area of any color, for example,

green, the line or area in the negative is dyed with a color complementary to green, namely, magenta. The system may be best understood by reference to the following table:

A photographic paper consisting of three emulsions coated on a support, each emulsion layer sensitive to light of one of the colors, red, green and blue, and each layer containing a color forming compound, is exposed in a printing frame in contact with the emulsion surface of the colored negative to white light with or without the use of filters over the light source. The dyes in the lines or areas of the negative serve as color filters which are in general adequate to print lines of satisfactory color and purity without the use of additional filters. A single exposure is sufiicient to print all of the colored lines. After exposure, the photographic color paper is then developed in a p-phenylene-diamine type developer, the reaction products of which couple with the color forming compounds contained in the emulsion layers of the photographic color paper, to give a print composed of lines or areas which are complementary to the colored lines or areas of the 1188815178.

2 The development of the above process has been attended with difliculties connected with the application of the dye coating compositions to the transparent lines or-areas of the negatiuewhich areto appear in color in the finished print. The aqueous 'or alcohol solutions of the dyes previously used are not satisfactory for coloring the negatives since they are difiicult to apply in sufficient density withreasonable speed. Further more, crystallization of the dye takes place upon drying. These dye solutions also have a tendency to run after application into uneven areas resulting in the formation of areas of unequal densityso that uneven color. lines or areas are obtained in the finished print.

It is an object of the present invention to overcome these and other undesirable characteristics and disadvantages, and to provide improved dye coating compositions, whereby colored negatives of desirable characteristic are obtained.

A further object is to provide a simplified process of converting black and white or monochrome drawlngs into multicolor photographs.

Other objects and advantages of this invention will be apparent by reference to the foregoing specificaiton, in which its preferred details and embodiments are described.

According to the present invention the above objects are accomplished by the preparation and use of dye coatlng'compositions of the following general composition:

Water soluble dye-..- grams 110 5-25% aqueous solution of hydrophilic polymer or -100 Water soluble aliphatic polyhydric alcohol containing at least two carbon atoms grams 0.5-1 Wetting agent do 0.5-1

' headings, which are grouped in the following list:

Acridine dyes, e. g., Acridine Orange R (C. I. #792) Phosphine 2G (0''. I. #794) Euchrysine 2G (0. I. #797), etc., Anthraquinone dyes, e. g., Alizarin Carmine (C. I 1034), Erweco Alizarin Acid RedSB (C. I. #1036) Pseudopurpurin (C'. I. #1043), etc., Azine dyes, e. g., Neutral Red (C. I.

#825), Neutral Violet (C. I. #876), Rosinduline G' (O. I. #831, etc., Azo dyes, e. g., Emin Red (0. I.

#132), Metanil Yellow (c. I. #138), Eriochrome Phosphine R (C. I. #157), Fast Light Yellow (C. I. #636), Kiton Fast Yellow 3G (C. I. #645), Pyrazolorange G (C. I. #653), Chloiazol Yellow GX (C. I. #620), Cotton Orange 6305 (C. I. #625) Direct Fast Orange BGL (C. I. #633), etc., Nitro dyes, e. g., Victoria Yellow (C. I. #8), Naphthol Yellow (C. I. #10), Amido Yellow (C. I. #11), etc., Oxazine dyes, e. g., Brilliant Blue CC (C. I. #876), Chromazurine E (C. I. #879), etc., Thiazine dyes, e. g., Genthianine (C. I. #921), Methylene Azure (C. I. #923), Indochromogen S (C. I. #930), and Triphenyl methane dyes, e. g., Turquoise Blue G (C. I. #661), Acid Green (C. I. #669), Xylene Blue AS (C. I. #673) and the like.

The above dyes were selected because of their brilliancy of color. The preferred dyes from the above group, however, are those which effectively transmit a sharply isolated spectral band while eliminating undesirable transmissions of a secondary spectral band. Thus, for example, the red dye which may be a mixture of Anthraquinone Rubine and Tartrazine, transmits freely in the red wave length beyond 600 m and is substantially opaque to the spectral region below 600 m The green dye which may be a mixture of Anthraquinone Blue SE and Tartrazine N transmits freely in the green wave length between 500 and 600 my. and is substantially opaque to other spectral regions. The blue dye which may be a mixture of Anthraquinone Blue SE and Fast Acid Violet B transmits freely in the blue wave length between 400 and 500 my and is substantially opaque to the longer wave lengths of the spectrum. The orange dye such as Pyrazolorange G transmits above 500 m and is substantially opaque to the shorter wave lengths of the spectrum. The magenta dye such as Anthraquinone Rubine transmits freely two bands, one in the blue region of 400-500 In, and the other band in the red region above 600 m and is opaque to the green region of the spectrum. The cyan dye such as Anthraquinone Blue SE transmits freely in the blue and green region between 400 and 600 m and is likewise opaque to the longer wave lengths of the spectrum. The actual selection of the preferred dyes is made by colorimetric methods which are well known to the art and need not be discussed herein, or by actually preparing the dye coating composition, coloring a negative and printing it out on color paper.

The cyan dyes suitable for forming red lines or areas in the finished print are, for example, Anthraquinone Blue SE (Schultz #861), Brilliant Alizarin Viridine F (Schultz #854) and Alizarin Cyanine Green F (Schultz #865).

The yellow dyes suitable for forming the blue lines or areas in the finished print are, for example, Pyrazolorange G (Schultz #747). Stilbene Yellow 3 GA (C. I. #622), Milling Yellow (Schultz #230). Erie Yellow Y (C. I. #365), Solantine Yellow FF (C. I. #814), Naphthol Yellow S (Schultz #7) and Tartrazine N (Schultz #23). i

The magenta dyes suitable for forming the green lines or areas in the finished print are, for example, Brilliant Congo G (Schultz #369), Geranine GL, Erie Pink 2 B (C. I. #128), Rose Bengal N (Schultz #595) Anthraquinone Rubine R (DuPont), Brilliant Purpurine 4 B (Schultz #368) and Brilliant Crocein B (Schultz #227).

Several re'd dyes may be obtained by blending magenta dyes with yellow dyes. Suitable greens may be obtained by blending cyan dyes, with yellow dyes. Suitable blue-violets may be obtained by blending cyan dyes with violet or magenta dyes. Similarly, the hue of the single dyes, yellow, magenta and cyan, may be adjusted to the requirements of the color paper by blending two dyes together.

The amount of dye employed in each coating composition will depend upon the amount of hydrophilic polymer used and the depth of shade required. The amount employed may range from 1 to 10 grams per cc. of the aqueous hydrophilic polymer. The desirable proportions, however, are in the range of 3 to 5 grams per 100 cc. of aqueous hydrophilic polymer.

The aqueous solution of hydrophilic polymer referred to in the above general composition acts both as a carrying and binding medium for the dyes. Suitable materials of this type are any of the natural gums and synthetic resins (polymers) which have an aiiinity for water and aque- 0115 media. The hydrophile radical of these gums and resins consists of hydroxy groups'or carboxy groups, or both, and imparts to the gum or polymer molecule of which it is a member, a tendency to be wetted by water and aqueous media. As typical illustrations of water swellable and water soluble hydrophilic gums and polymers may be mentioned gum acacia, gum grindelia, gum tragacanth, irish moss, polyvinyl alcohol, Water soluble polyvinyl acetals, sodium salt of cellulose glycolate, sodium salt of carboxy ethyl cellulose, and Elastolac, a resin obtained by the intermolecular polycondensation of aleuritic acid CH2 (OH) .(CH2) 5 .CHOH.CHOH.(CH2) 7 .COOH. These hydrophilic gum materials are well known in the art, and as for the polyvinyl alcohol, water soluble polyvinyl acetals, and the sodium salts of the polymeric celluloses, suitable methods for their preparation have been described in the literature.

The water soluble aliphatic polyhydric alcohols which act as spreading agents for the dye carrying medium (dye and aqueous hydrophilic polymer) contain at least 2 carbon atoms and are either liquid per se or if solid are soluble in water. As suitablepolyhydric alcohols may be mentioned, ethylene glycol, trimethylene glycol, propylene glycol, glycol di-glycolate, glycerol, i-erythritol, di-arabitol, xylitol, rhamnitol, dulcltol, d-mannitol and d-sorbitol. The principal function of these polyhydric alcohols is to assist in spreading the dye carrying medium evenly over the negative and to prevent cracking thereof after application to the negative upon drying.

Suitable wetting agents that are employed in dispersing the dye in the dye carrying and binding medium, and at the same time preventing the partial precipitation or sedimentation of the dye in solution are, alkylated mono sodium benzenesuifonate, di-hexyl ester of sodium sulfosuccinate, sodium salt of an alkyl naphthalene sulfonlc acid, sodium salt of tetrahydronaphthalene sulfonic acid, calcium glycerin phosphate, alkylphenyl polyethylene glycol, oleic acid ester of hydroxyethane sulfonic acid and sulfonated higher mo-. lecular weight primary or secondary aliphatic, aromatic and cycle-aliphatic carboxy acids. It is to be noted, however, that any commercially available wetting agent may be employed. The nature of the wetting agent is immaterial so long as it possesses wetting, dispersing and emulsifying properties, and its aqueous solutions are colorless or only slightly tinted.

In carrying out the invention into practice it.

. is first preferred to swell or dissolve the hydrophilic polymer in water at room temperature for several hours. The solution is then heated gently at a temperature not exceeding 50 C. with stirring for a few minutes and then allowed to cool until all the air bubbles have escaped and the solution brought to the desired volume by the additicn of water. In preparing the dye coating composition, a paste is made of the dye by mixing it with a small quantity of a warm aqueous solution of the hydrophilic polymer material until the dye is wetted. The remainder of the aqueous solution of the hydrophilic polymer material is then added and brought to the desired volume, after which the requisite quantity of a water soluble aliphatic polyhydric alcohol and wetting agent is added.

The following examples are illustrative of the manner in which compositions of this invention are prepared.

"Exam ne I w (Blue-Violet dye) Anthraquinone Blue SE (Schultz #861) grams 3.0 Fast Acid Violet B (Schultz #580) do 1.5 Polyvinyl alcohol 15% solution cc 100 Glycerin grams 1 Sodium salt of sulfonated ethyl oleate do 1 ExsmrmII (Yellow dye) Pyrazolorange G (Schultz #747 ..grams 2 Sodium salt of cellulose glycolate 20% solution cc d-Sorbitol 40% solution. grams 1.5 Sodium salt of tetrahydronaphthalene sulfonic acid grams- 0.5

' Examrmm (Magenta dye) Brilliant Congo G (Schultz #369) grams 1.5 Sodium salt of carboxy ethyl cellulose 10% solution c..- 50 d-Mannitol 40% solution; grams 1.5 Sodium salt of isopropyl naphthalene sulfonic acid grams.- 0.5

was copied on a high contrast photographic film so as to obtain high densities and clean white lines. After exposure, the film was developed in the usual developing solution, fixed, washed and dried. The dried negative was then temporarily cemented, emulsion downwards on a piece of glass. The film negative and glass were then placed on a light table in a reasonably level position. The light table was fitted with daylight fluorescent tubes in order to obtain desirable color quality for judgment of color densities. The film negative was then cleaned with a cloth moistened with ethyl alcohol in order to prepare it for even dyeing.

The above blue-violet, yellow and magenta dye coating compositions were then applied evenly over the white lines of the negative which are to appear as yellow, blue and green respectively in the final print. The dye coating solutions were applied by means of a small spotting brush, the sharp needle point of which was cut ofl, so as to 6 confine the dye substantially to the line being colored; that is, without substantially overlapping the white line, or forming areas of excess dye adjoining the white line. One application with the brush fully charged with each of the dyes to the lines being colored, was adequate to ,obtain suflicient color density. The applied dye coating solution was permitted to flow naturally in order to obtain even spreading. Between colors, the brush was rinsed in a glass of water and dried on a cloth. After application of the dyes, 3 to 5 minutes were required for thor-. ough drying, following which the negativ was removed from the glass for printing.

An examination of the above colored negative showed that the dye coatings were thoroughly dry and did not crack or the dyes crystallize out. All the colored lines were satisfactorily smooth and even. The colored negative was then contact printed on a three super-imposed emulsion layer photographic color paper, emulsion to emulsion in a printing frame, six feet from a 60-watt frosted mazda lamp. The exposure time was approximately 10 seconds. The exposed color paper was then developed in a developer of the following composition:

p-Aminodiethylaniline HCl grams 2.0 Sodium carbonate (anhydrous) do 50.0 Sodium sulfite (anhydrous) --do 2.0 Potassium bromide -do 0.2 Water to make -liters 1' After bleaching, fixing, washing and drying, the, resulting print showed no unevenness in the colored lines. All the colored lines were smooth and of pure color. a

The photographic multilayer element (color, paper) or other printing material used in carry-, ing out the process described in the present invention consists of an integral tripack emulsion coated on either the usual paper base, or a clear cellulose acetate or nitrate film base, or in some cases an opaque white film base. Each of the emulsion layers is sensitized to one of the primary colors of light; namely, blue, green and red. The top layer is blue sensitive. A filter layer, yellow in color and blue absorbing. lies under the top layer. Below this filter layer, lies a green sensitive emulsion layer, and below this a red sensitive emulsion layer. Eachof the three silver halide emulsion' layers contain dye-forming compounds which unite during the development of a silver image in an aromatic amine developing agent to form a dye with the oxidation product of the developing agent. As silver is also formed during development, it must be removed after color development by treatment in a bleach, followed by a bath of sodium thiosulfate, as is well known to the art. A yellow dye is formed in the blue sensitive emulsion; a magenta dye is formed in the green sensitive emulsion; and a cyan dye is formed in the red sensitive emulsion. The combinations of these three printing primaries yield red, green, blue and black lines. Suitable methods for the preparation of multicolor emulsion. layers have been described in the literature relating to color photography, and are, therefore, not described here.

The dye coating compositions of the present invention are not limited to the coloring of a black and white film negative given above, such being merely illustrative of the manner of employing the dye coating compositions of this invention.

Instead of coating black and white negatives, the dye coating compositions of the present in- The dye coating compositions may also be emplayed for retouching or repairing damaged areas of colored photographs such as transparencies or paper prints. The various dye coating compositions may be mixed on a piece of opal glass with a small brush to match the prevailing color or the.

area surrounding the blemish. The dye is then applied with the brush to the blemish. 0n drying, the dye will assume the surface characteristics of the gelatine image-bearing layer, and the repaired or retouched area will not be readily detectable.

By the term hydrophilic polymer" as used hereinabove and in the appended claims, we intend to designate water swellable or water soluble natural gums which yield on hydrolysis a mixture of aldohexoses'and hexuronic acids. This term likewise designates the synthetic resins (polymers) the character of which manifests itself by the presence of hydroxy or carboxy hydrophile radicals which impart to the polymer molecule, of which either one or both of said radicals is a member, a tendency to be wetted by water and aqueous media.

- While we have herein disclosed the preferred embodiments of our invention, we do not thereby desire or intend to limit ourselves solely to the specific examples, since it will be readily apparent to those skilled in the art, that the precise proportions of the materials utilized may be varled and other materials having equivalent chemical or physical properties may be employed if desired without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claim. We claim:

7 A dye coating composition for color photography consisting of a dispersion of:

Anthraquinone Blue SE (Schultz #861) grams- Fast Acid Violet B (Schultz #580) do Polyvinyl alcohol 15% solution. ..cc..- Glycerin ..-srams-- sodium salt of sulfonated ethyl oieate-do-..--

. HAROLD C. HARSH.

RICHARD M. I-IAFF. FRANK J. KABZUBA.

REFERENCE/SACRED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

